California 
Reserve 


UNIVERSI1    '    Of     CALIFORNIA 

COLLEGE    OF    AGRICULTURE 

AGRICULTURAL    EXPERIMENT    STATION 

BERKELEY,    CALIFORNIA 

CIRCULAR  115 

February,  1914 
(Eevised  November,  1927) 

GRAFTING  VINIFERA  VINEYARDS 

FREDERIC  T.  BIOLETTP 
Revision  by  H.  E.  JACOB- 


Grafting  has  two  principal  uses  in  grape-growing':  (1)  to  change 
the  variety  of  fruit  in  a  bearing  vineyard;  and  (2)  to  establish  a  new 
vineyard  on  phylloxera-resistant  roots.  Different  methods  are  needed 
in  each  case.  Only  methods  for  changing  the  variety  in  an  established 
vineyard  are  described  here.3 

Reasons  for  Changing  Variety. — When  grafting  is  done  to  change 
the  variety,  the  purpose  is  usually  to  replace  an  unprofitable  variety 
with  one  that  has  a  better  market  or  one  more  suitable  for  the  soil  or 
climate.  Before  doing  this  it  is  advisable  to  consider  carefully  the 
chances  of  success. 

The  cost  of  grafting  and  the  care  of  the  vineyard  until  it  comes 
into  bearing  again  is  almost  as  great  as  the  cost  of  replacing  the  old' 
vines  with  new  vines  of  the  desired  variety.  The  only  advantage  of 
grafting  is  that  the  vines  bear  one  or  two  years  sooner.  Unless,  there- 
fore, the  chances  seem  very  great  that  the  first  two  or  three  crops  of 
the  new  kind  of  grape  will  pay  all  the  expenses  of  transforming  the 
vineyard  and  of  the  deterioration  and  shortening  of  the  life  of  the 
vineyard,  grafting  is  inadvisable. 

Grafting  may  also  be  used  to  change  undesirable  varieties  in  mixed 
blocks.  Scattered  wine  grapes  in  a  vineyard  of  table  grapes  or  raisin 
grapes  are  wasted  or  are  expensive  to  harvest.  These  can  be  best 
utilized  by  grafting  with  the  variety  of  which  the  block  is  mainly 
composed. 

Grafting  is  also  a  very  effective  means  of  rapidly  increasing  the 
stock  of  cuttings  for  propagating  new  or  rare  varieties. 

There  are  cases,  therefore,  where  a  change  of  this  kind  is  advisable. 
At  all  events  there  is  always  somebody  ready  to  take  the  risk,  and  it 
is  advisable  to  make  this  risk  as  small  as  possible  by  doing  the  work 
properly. 


1  Professor  of  Viticulture  and  Viticulturist  in  the  Experiment  Station. 

2  Junior  Viticulturist  in  the  Experiment  Station. 

3  Methods  suitable  for  resistant  roots  can  be  found  described  in:  Bonnet,  L.  (). 
Phylloxera  resistant  vineyards.     California  Agr.  Exp.  Sta.  Cir.  288:1-24.     1925. 


2  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

Age  of  Vines. — Vinifera  vines  may  be  grafted  at  any  age,  but  there 
is  seldom  anything  to  be  gained  by  grafting  vines  less  than  two  or 
three  years  old.  For  yonnger  vines,  it  is  usually  cheaper  and  better 
to  dig  up  and  replant,  if  a  change  is  necessary.  Old  vines  (twelve 
years  old  or  over)  may  be  grafted  successfully  if  they  are  sound  and 
straight  below  the  soil.  Such  grafted  vines,  however,  are  usually 
short-lived.  The  large  wounds  and  the  great  amount  of  wood  which 
decays  often  make  unhealthy  vines.  In  deep,  loose,  dry  soil  the  stumps 
of  such  vines  may  be  removed  entirely  and  the  grafts  inserted  in  the 
roots.  This  requires  great  skill,  however,  and  the  percentage  of 
failures  is  always  large.  Vines  from  three  to  eight  years  old  are  the 
most  easily  and  successfully  grafted. 

Choice  of  Scions. — Preparation  for  grafting  should  be  started  early 
by  choosing  strong,  healthy  vines  of  the  desired  variety,  from  which 
to  take  the  cuttings  to  be  used  as  scions.  The  failure  of  grafts  is  often 
due  to  the  use  of  inferior  scion  wood.  The  cuttings  should  be  taken 
from  the  vines  when  they  are  dormant.  Any  time  between  one  or  two 
weeks  after  the  leaves  have  fallen  and  a  month  before  the  swelling  of 
the  buds,  is  suitable.  However,  cuttings  taken  within  a  few  weeks 
after  the  fall  of  the  leaves  are  the  best. 

The  cuttings  should  be  carefully  selected  and  only  good  sound 
canes  of  medium  size  and  firm  texture,  well  nourished  and  mature, 
with  well-formed  eyes  neither  too  close  together  nor  too  far  apart, 
should  be  used. 

Conservation  of  Scion  Material. — It  is  convenient  to  make  the 
cuttings  long  enough  for  two  scions,  allowing  two  extra  eyes  for  waste. 
The  length  will  be  from  14  to  24  inches  according  to  the  variety  and 
the  length  of  scion  used.  The  cuttings  should  be  made  up  into  bundles 
of  from  fifty  to  one  hundred  and  stored  in  a  cool  and  moderately  dry 
place.  The  best  way  is  to  put  them  into  pits  or  trenches  under  an 
open  shed,  and  cover  them  completely  with  very  slightly  moist  sand. 
Any  shady  place  where  there  is  no  danger  of  too  much  moisture 
getting  to  the  cuttings  may  be  used,  such  as  under  a  dense  tree,  the 
north  side  of  a  building,  or  a  cellar. 

Season  for  Grafting. — The  best  time  for  grafting  depends  some- 
what on  the  soil  and  the  climate,  but  usually  the  latest  grafts  do  the 
best,  provided  the  scions  are  completely  dormant  and  otherwise  in 
good  condition.  If  the  buds  of  the  scions  have  started  and  the  bark 
has  loosened,  many  will  fail. 

In  well  drained,  sandy  soil,  the  time  for  successful  grafting  extends 
from  January  to  May  in  most  localities,  but  March  for  the  earlier 
and  April  for  the  later  localities  are  usually  the  best  months.  In  stiff, 
wet  soils,  much  greater  care  is  necessary  in  choosing  the  time  for 
grafting.  The  soil  should  be  in  such  condition  that  it  will  pulverize 
easily,  and  the  heavy  rains  should  be  over.  Lumpy  soil  placed  about 
the  graft  will  cause  many  failures,  and  a  heavy  rain  which  leaves  the 
soil  water-logged  around  the  union  for  several  days  may  kill  all  the 
grafts.  On  the  other  hand,  in  the  drier  and  hotter  districts,  it  is  often 
necessary  to  irrigate  the  grafts  before  they  start,  especially  with  late 


Circ.  115] 


GRAFTING    VINIFERA    VINEYARDS 


grafting.  The  soil  in  contact  with  the  lower  part  of  the  scion  should 
never  become  dry  until  the  union  has  formed. 

It  is  best  whenever  posisble  to  wait  until  the  buds  begin  to  swell 
on  the  vines  to  be  grafted,  and  grafting  may  continue  until  the  shoots 
are  several  inches  long. 

Methods  of  Grafting. — Many  methods  have  been  recommended  and 
used  for  old  vines,  but  only  two  need  be  described  here :  (1)  the  ordi- 
nary cleft  graft  (fig.  2,  C,  D,  and  E)  and  (2)  the  groove  graft  (fig.  2, 
F,  G,  K,  and  L) .  Neither  of  these  methods  is  difficult  and  either,  if 
done  under  proper  conditions,  should  give  practically  a  perfect  stand. 
The  cleft  graft  is  the  best  known  in  California  and  is  therefore  most 
commonly  used,  but  the  groove  graft,  since  it  avoids  the  splitting  of 
the  stump  and  hence  offers  less  opportunity  for  entrance  of  decay- 
causing  organisms,  should  theoretically  produce  a  longer-lived  vine. 


Fig.  1. — Tools  for  grafting:  pruning  saw,  knife,  special  grafting 
tool,  chisel,  and  wooden  maul. 


Tools  Necessary. — For  cleft  grafting,  the  special  tools  needed  are  a 
curved  vine-pruning  saw,  a  grafting  or  budding  knife,  a  wooden  maul, 
and  a  strong  half -inch  mortising  chisel.  If  the  vines  are  very  large, 
that  is,  over  3  inches  in  diameter,  it  is  well  to  have  a  grafting  tool 
made.  Any  blacksmith  can  make  a  good  one  from  an  old  horseshoe 
file.  This  tool  should  be  14  inches  long.  At  one  end  it  should  be 
flattened  out  into  a  hatchet-shaped  blade  3  inches  long  and  2  inches 
wide.  This  blade  should  be  about  %-inch  thick  on  the  back,  gradually 
tapering  to  a  sharp  edge.  The  other  end  of  the  tool  should  be  shaped 
like  a  cold  chisel  about  %-inch  wide.  This  cold-chisel  edge  should  be 
in  the  same  plane  as  the  hatchet  edge  (see  fig.  1)  and  not  at  right 
angles  to  it  as  it  is  sometimes  made.  For  the  groove  graft  only  the 
saw,  grafting  knife,  and  a  light  hammer'  are  needed. 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


K 


Pig.  2. — Operations  of  grafting.    These  operations  are  explained 

in    tlie    text. 


ClRC.  115]  GRAFTING    VINIFERA    VINEYARDS  .") 

A  convenient  receptacle  for  holding  the  scions  is  made  by  cutting 
a  five-gallon  kerosene  can  horizontally  through  the  middle  and  placing 
a  round  stick  across  the  top  for  a  handle.  This  will  hold  fifty  or  more 
scions.  By  putting  an  inch  of  water  in  the  bottom,  they  can  be  kept 
perfectly  fresh. 

Preparation  of  the  Stock. — The  first  step  is  to  clear  away  the  earth 
from  around  the  base  of  the  vine,  making  a  pit  about  2  feet  in  diameter 
and  3  or  4  inches  deeper  than  the  level  at  which  the  grafting  is  to  be 
done.  The  earth  should  be  well  cleaned  off  the  stem  of  the  vine  and 
the  rough  dry  bark  removed  {A,  fig.  2).  The  vine  is  then  ready  for 
decapitation.  This  should  be  done  by  sawing  horizontally  in  such  a 
place  that  about  2  inches  of  smooth,  straight  grain  are  left  at  the  top 
{S,  fig.  2).  If  the  sawing  is  done  at  or  too  near  a  place  where  the 
grain  of  the  wood  is  crooked  or  curly,  great  difficulty  will  be  found 
by  the  grafter  in  making  a  good  fit,  particularly  with  cleft  grafting. 
The  amount  of  sap  that  will  flow  out  of  a  vine  2  inches  or  more  in 
diameter  is  considerable,  sufficient  in  many  cases  to  kill  the  graft. 
This  may  be  avoided  by  cutting  off  the  vines  one  or  two  days  before 
grafting  and  leaving  them  exposed  in  order  that  the  main  flow  of  sap 
may  drain  away.  This  is  good  practice  in  all  cases  where  the  vines 
are  over  1%  inches  in  diameter. 

Preparation  of  the  Scions. — Proper  care  of  the  scions  is  necessar}T 
for  the  best  results.  If  the  cuttings  have  been  made  and  kept  properly, 
they  will  show,  on  being  cut,  clear  greenish-white  wood,  green  inner 
bark,  and  firm,  dry,  light-brown  pith.  If  the  wood  is  streaked  or 
spotted  with  black,  the  bark  loose  or  brownish,  or  the  pith  black  or 
water-soaked,  the  cuttings  have  been  injured  by  too  much  moisture,  or 
they  were  poor  cuttings  to  begin  with,  and  should  not  be  used. 

Cuttings  which  are  too  dry  are  harder  to  detect  by  their  appear- 
ance. If  suspected  of  being  too  dry,  they  may  be  tested  by  placing 
two  or  three  short  pieces  of  two  or  three  buds  each  in  moist  sand  in 
a  warm  room.  If  in  a  week  the  roots  do  not  start  nor  the  buds  swell, 
they  are  unsafe  to  use. 

Twenty-four  hours  before  they  are  needed,  the  cuttings  should  be 
taken  out  of  the  sand  in  which  they  have  been  stored,  and  washed  to 
remove  all  particles  of  sand,  which  would  dull  the  grafting  knife. 
They  should  then  stand  in  fresh  water  for  one  or  two  days,  but  not 
more,  until  used. 

Cleft  Graft. — In  making  the  cleft,  a  place  should  be  chosen  where 
the  bark  is  smooth,  straight,  and  sound.  The  cleft  should  be  made  by 
splitting,  not  by  cutting.  The  edge  of  the  knife  or  grafting  tool  should 
first  be  placed  on  the  part  of  the  sawed  surface  where  the  cleft  is  to 
be  made,  and  which  has  been  previously  cleaned  and  smoothed  with 
the  grafting  knife.  With  a  slight  blow  of  the  wooden  mallet  the  edge 
should  be  driven  about  Vs  inch  into  both  wood  and  bark  (0,  fig.  2). 
The  object  of  the  mark  thus  made  is  to  insure  that  the  bark  and  the 
wood  split  at  the  same  place.  The  chisel  or  the  chisel  end  of  the 
grafting  tool  should  then  be  placed  on  the  mark  sufficiently  far  from 
the  bark  to  allow  of  the  insertion  of  the  scion,  and  driven  in  an  inch 


b  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

or  so,  sufficient  to  open  a  cleft  wide  enough  to  allow  the  entrance  of 
the  scion  (D,  fig.  2).  The  opening  of  the  cleft  is  accomplished  by 
pressing  the  chisel  sideways.  The  scion  should  then  be  inserted.  When 
the  chisel  is  released  and  removed,  the  tension  of  the  wood  will  hold 
the  scion  firmly  in  place  (E,  fig.  2). 

The  cleft  should  not  extend  quite  across  the  stock,  because  if  the 
cleft  extends  only  part  way,  it  will  close  up  more  completely  and  hold 
the  scion  more  firmly.  With  small  vines,  it  is  impossible  to  avoid 
splitting  quite  across.  With  very  small  vines  it  may  be  necessary  to 
tie  the  scion  in  by  putting  two  or  three  turns  of  thin  string  or  raffia 
around  the  stock.  With  very  large  vines,  the  pressure  is  occasionally 
sufficient  to  crush  the  scion.  This  is  obviated  by  placing  a  small  wedge 
of  wood  immediately  behind  the  scion. 

The  scion  is  cut  in  wedge  form,  a  little  thicker  on  the  side  which 
comes  nearest  to  the  bark.  The  length  of  the  wedge  depends  on  the 
character  and  size  of  the  cleft  in  the  stock.  The  wedge  wTill  usually 
be  long  and  tapering.  It  is  inserted  in  such  a  way  that  the  line 
between  the  bark  and  wood  coincide  with  the  corresponding  line  on  the 
stock.  As  the  bark  of  the  stock  is  thicker  than  that  of  the  scion,  the 
outer  surface  of  the  scion  will  be  set  in  slightly  from  that  of  the  stock. 
It  is  not  always  possible  to  make  the  lines  correspond  exactly,  but 
perfectly  satisfactory  unions  are  obtained  if  these  lines  are  very  near 
together  or  cross  in  one  or  two  places. 

The  cutting  of  the  scion  should  be  done  with  a  very  sharp,  clean 
knife,  and  its  insertion  in  the  stock  should  be  immediate,  before  it  has 
a  chance  to  become  dry  even  on  the  surface.  It  is  bad  practice  to 
prepare  the  scions  beforehand. 

If  the  vines  are  1%  inches  in  diameter  or  less,  one  scion  to  each 
vine  is  sufficient.  An  attempt  to  insert  more  will  usually  result  in 
having  two  badly  fitting  grafts  in  place  of  one  good  one.  For  larger 
vines,  two  scions  are  preferable  whenever  they  can  both  be  made  to  fit 
securely.  If  both  of  them  grow,  the  weaker  is  removed  at  the  next 
pruning.  It  will  have  served  a  good  purpose  in  helping  to  heal  the 
grafting  wound. 

Groove  Graft. — This  differs  from  the  cleft  graft  in  the  shape  of 
the  scion  and  the  method  of  inserting  it.  Instead  of  being  wedge- 
shaped  and  inserted  in  a  cleft  or  split  of  the  stock,  the  scions  are 
shaped  to  fit  into  a  V-shaped  groove  on  the  side  of  the  stock  extend- 
ing from  the  top  of  the  stump  downward  from  1  to  1%  inches.  The 
width  and  the  depth  of  the  groove  at  the  top  should  be  the  same  as 
the  diameter  of  the  scion  to  be  used,  or  slightly  less.  The  groove 
tapers  to  a  point  at  the  bottom.  The  scion  should  be  fitted  into  the 
groove  so  that  the  cambium  layer  of  the  scion  and  of  the  stock  coincide 
as  completely  as  possible. 

The  groove  in  the  stock  is  most  conveniently  formed  by  first  mak- 
ing a  shallow,  straight  saw  cut  as  long  and  as  deep  as  the  groove  is  to 
be  (F,  fig.  2).  Then  by  means  of  a  sharp  knife  the  groove  is  widened 
at  the  top  and  tapered  to  a  point  at  the  bottom  (G,  fig.  2).  When 
finished,  the  cut  surface  should  be  smooth  and  straight.  If  it  is  rough 
and  irregular,  a  good  fit  with  the  scion  cannot  be  secured. 


CIRC.  115]  GRAFTING    VINIFERA   VINEYARDS  7 

The  scion  should  be  shaped  so  that  the  cambiums  of  the  stock  and 
scion  coincide  when  it  is  placed  in  the  groove.  The  angle  that  the 
cuts  of  the  scion  make  with  one  another  should  be  slightly  more  obtuse 
than  the  angle  of  the  groove.  Thus,  when  the  scion  is  placed  on  the 
stock,  the  contact  will  be  firm  at  the  line  of  the  bark,  which  will 
insure  close  contact  of  the  cambiums.  Figure  2,  K,  shows  a  scion 
properly  shaped  to  fit  the  groove  in  the  stock  (fig.  2,  G). 

After  inserting  the  scion  in  the  groove,  it  should  be  held  firmly  in 
place  until  the  tissues  grow  together.  This  can  be  accomplished  most 
easily  by  nailing  it  with  one  or  two  1-inch  19-gauge,  flat-headed  wire 
nails  (L,  fig.  2). 

Length  of  the  Scion. — It  is  usual  to  use  scions  of  two  buds,  but 
there  is  often  an  advantage  in  having  them  longer.  Three  and  even 
more  buds  have  been  used  with  advantage  on  large  vines.  With  only 
two  buds  on  such  vines  the  growth  is  often  so  rapid  and  so  large  as  to 
be  almost  unmanageable.  With  several  buds  the  growth  is  divided 
between  more  shoots  and  they  are  less  likely  to  grow  so  large  as  to  be 
troublesome. 

Covering  the  Scion. — As  soon  as  the  scion  is  in  place,  all  cut  sur- 
faces of  stock  and  scion  should  be  carefully  covered  with  a  couple  of 
inches  of  moist,  well-pulverized  soil  (H,  fig.  2),  and  a  stake  driven 
in  such  a  position  that  it  will  support  the  first  growth  of  the  graft. 
The  complete  filling  of  the  hole  may  be  deferred  for  a  few  hours,  but 
not  long  enough  to  run  any  risk  of  having  the  scion  become  even 
slightly  dry;  in  extremely  hot,  dry  weather  the  hole  should  be  filled 
immediately.  No  wax,  clay,  or  similar  material  is  needed  unless  the 
cleft  is  large.  There  is  nothing  better  to  put  around  the  union  than 
moist,  loose  soil.  This  gives  the  conditions  of  moisture  and  aeration 
most  favorable  to  the  uniting  of  the  tissues.  With  a  cleft  graft  it  is 
a  good  practice  to  cover  the  cleft  in  the  stock  with  a  little  clay,  a  leaf, 
or  anything  that  will  exclude  the  soil,  but  unless  the  cleft  is  large,  this 
is  not  necessary.  It  is  never  necessary  with  the  groove  graft.  The 
filling  of  the  hole  with  soil  should  be  complete ;  the  whole  scion  may  be 
covered  up  unless  the  soil  has  a  tendency  to  bake.  When  finished, 
each  graft  will  be  in  the  middle  of  a  wide  mound  of  soil  (H2,  fig.  2). 
Narrow  mounds  may  become  too  dry. 

After-Treatment  of  the  Grafts. — The  proper  management  of  the 
grafts  during  the  first  growing  season  is  as  important  as  the  grafting 
itself. 

The  mounds  should  not  be  disturbed  by  hoe  or  cultivator  until  the 
unions  are  well  formed.  If  the  scions  are  completely  covered  and  the 
mounds  form  a  hard  crust,  this  crust  should  be  carefully  broken  with 
the  fingers. 

Suckering. — Many  large,  vigorous  shoots  will  come  up  from  the 
old  stock.  If  these  are  left  too  long,  they  will  choke  or  dwarf  the 
graft.  If  they  are  removed  too  soon,  many  good  grafts  will  be  killed 
by  injuring  the  unions.  Judgment  and  careful  work  are  therefore 
needed  in  suckering.  When  the  grafts  have  started  to  grow  vigorously, 
so  that  the  shoots  can  be  tied  to  the  stake,  it  is  safe  to  begin  suckering. 


8  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

At  this  time  the  suckers  can  usually  be  pulled  up  by  the  hand  in 
bunches,  without  removing  any  soil.  Unless  it  is  certain  that  the 
suckers  are  not  entangled  with  the  scion,  some  soil  must  be  carefully 
removed  until  it  is  possible  to  see  how  to  detach  the  suckers  without 
disturbing  the  union. 

If  grafts  are  slow  in  starting,  and  the  suckers  vigorous,  it  is  neces- 
sary to  sucker  before  the  scion  has  grown  much.  This  can  be  done 
safely  if  care  is  used. 

Tying  up  the  Shoots. — When  the  union  is  complete,  the  growth  of 
the  grafts  on  large  vines  is  generally  very  rapid.  A  growth  of  2  or  3 
inches  a  day  is  common,  and  many  canes  grow  10  to  15  feet  by  the 
end  of  the  season.  Unless  this  vigorous  growth  is  properly  managed, 
not  only  are  its  benefits  lost,  but  it  also  gives  great  trouble  the  follow- 
ing year  and  makes  it  impossible  to  obtain  a  properly  shaped,  healthy 
vine.  If  the  canes  are  left  to  themselves  they  will  often  grow  flat  on 
the  ground.  As  they  may  be  1%  inches  thick  or  more  by  the  end  of 
the  season,  the  attempt  to  raise  them  up  the  next  year  will  result  in 
tearing  many  of  the  finest  grafts  out  of  the  stock,  and  the  rest  will 
make  ill-shaped  vines,  weakened  by  numerous  large  wounds. 

The  shoots  should,  therefore,  be  tied  loosely  to  the  stake  with  a 
piece  of  string  or  thin  rope  as  soon  as  they  are  long  enough.  If  too 
many  shoots  start,  they  should  be  thinned.  This  thinning  should  be 
done  early  in  order  to  throw  all  the  available  strength  and  growth  into 
shoots  left.  One  shoot  to  each  bud  is  enough  on  strong  vines,  and 
one  shoot  to  a  graft  on  weak  or  small  vines. 

The  management  of  the  shoots  from  this  time  is  exactly  the  same 
as  for  exceptionally  vigorous  ungraftecl  vines.  A  well  placed  vigorous 
shoot  is  selected  and  tied  carefully  to  the  stake  until  it  is  a  little  higher 
than  the  desired  head  of  the  vine.  It  is  then  cut  back  to  a  point  two 
or  three  inches  above  the  point  of  heading.  For  unilateral  cordon 
vines,  the  shoot  is  trained  along  the  wire  and  this  cutting  back  is  not 
done  until  the  shoot  reaches  the  extreme  length  of  the  cordon.  For 
bilateral  cordons  the  cutting  back  is  done  so  that  the  point  where  the 
trunk  should  divide  into  its  two  branches  is  between  the  two  highest 
buds  left.4  When  this  cutting  back  of  the  selected  shoot  is  done  all 
other  long  or  vigorous  shoots  should  be  cut  back  at  the  same  time.  The 
laterals  which  start  less  than  8  or  10  inches  from  the  base  of  the  main 
shoot  should  be  pinched  off  when  small,  but  all  laterals  above  that 
should  be  allowed  to  grow.  The  new  vine  is  thus  completely  formed 
the  first  season,  the  main  shoot  forming  the  trunk  of  the  vine  and  the 
laterals  the  branches.  Such  a  vine  may  produce  almost  a  full  crop  the 
following  year. 

Cost  of  Grafting. — The  cost  of  grafting  over  an  old  vineyard 
properly  will  in  all  cases  be  heavy,  and  will  seldom  be  less  than  $35 
per  1000  vines  above  the  ordinary  cost  of  cultivation,  and  without 
reckoning  the  cost  of  stakes  and  the  loss  of  crop.  With  large  vines 
the  cost  may  considerably  exceed  this. 


4  For  fuller   directions   see  Bioletti,   Frederic   T.,   and   H.   E.  Jacob.     Head, 
cane,  and  cordon  pruning  of  vines.    California  Agr.  Exp.  Sta.  Cir.  277:1-32.    1!)24. 


